External spring retaining rings functioning when assembled in grooves provided for their reception in shafts, rods, posts and like cylindrical members as artificial shoulders for locating machine parts such as gears, bearing races, etc. in axial position thereon are well known and have received wide acceptance in industry. However, in attempting to extend the fields of their use it was learned that such rings when of the conventional design lack the surface area and shoulder-height requisite to the artificial shoulder provided thereby also serving as a positive stop for an abutting part likely to work itself loose, such as a nut threaded on a correspondingly threaded end of a shaft or post member. The obvious changes in ring structure designed to provide the ring body with the added surface area and greater shoulder height necessary to the ring being capable of functioning as a positive stop for use in the aforementioned special applications were unsatisfactory because said changes resulted in a ring lacking the flexibility required for proper ring functioning.
Thus, the problem requiring solution was one of devising an external spring retaining ring having surface area and shoulder height, effective or real, enabling the ring when sprung into a groove provided therefor in a shaft, post or like cylindrical member, to function as a positive stop for an abutting part, such as a nut which is subjected to friction forces from working itself loose (backing off) from said member, while maintaining the flexibility of the ring body necessary to the ring being assembled in and disassembled from its groove without taking on a permanent set.